Abstract
We study central simple algebras with involution of the first kind that become hyperbolic over the function field of the conic associated to a given quaternion algebra Q. We classify these algebras in degree 4 and give an example of such a division algebra with orthogonal involution of degree 8 that does not contain (Q,−), even though it contains Q and is totally decomposable into a tensor product of quaternion algebras.
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The first author thanks S. Garibaldi and Ph. Gille for motivating discussions and the Université Catholique de Louvain for its hospitality during the preparation of this paper. The second author gratefully acknowledges the hospitality of Université Paris 13, where part of the work leading to this paper was carried out. He was supported in part by the F.R.S.-FNRS. Both authors acknowledge support from Wallonie-Bruxelles International and the French goverment in the framework of “Partenariats Hubert Currien.” They thank the referee for his careful reading of the paper and valuable advice.
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Quéguiner-Mathieu, A., Tignol, JP. Algebras with involution that become hyperbolic over the function field of a conic. Isr. J. Math. 180, 317–344 (2010). https://doi.org/10.1007/s11856-010-0106-x
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DOI: https://doi.org/10.1007/s11856-010-0106-x